this command is used for coand line calculator
$ echo "12+5" |bc
to do mathematical operations
$ bc
bc command along echo
$ echo 3+3 | bc
we can set the number of decimal values to be displayed by using the scale parfameter
$ echo 'scale=4 100/19' | bc
we can get the output of a file
bc < cal.txt
it does the mathematical operations
$ echo "X=10; X+=10;X" | bc
it does the mathematical operations
$ echo " X=14; X*=2; X" | bc
it does boolean operations
$ echo "11>=7" |bc
it does boolean operations
$ echo " 16<=8" | bc
it does boolean operations
$ echo " 16<=8" | bc